Web with sealed pockets

ABSTRACT

A web is formed from two sheets of polymeric material. An upper sheet includes pockets of any form. A lower sheet is subsequently bonded to the upper sheet which causes the sealing of each of the pockets. A web thus formed may be laminated with a metallic foil or metallized polymeric film. Such a web may also be laminated with a similar web in a face to face relationship so that the pockets interdigitate.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention pertains to webs or sheets that include sealed pockets.More particularly, the invention pertains to laminates formed from suchwebs.

2. Description of the Related Art

International Patent Application No. PCT/AU98/00494 (InternationalPublication No. W099/00161) discloses a protector pad which is formedfrom a web which is fabricated to include a number of sealed bubbleswhich provide a shock absorbing effect. That document is incorporatedherewith by reference.

BRIEF SUMMARY OF THE INVENTION

The present invention proposes certain improvements which allow theinvention to be employed in new fields and in new ways.

Accordingly, there is provided a web, comprising: two sheets ofpolymeric material, with a first sheet having an array of pockets formedinto it, and a second sheet bonded to the first sheet so as to seal thepockets.

In another embodiment of the invention, a laminate is formed from twowebs, each comprising overlying sheets of flexible material sealedtogether with a plurality of spaced apart, non-connected, air-filledpockets. Each web further comprises a flat side and a pocketed side. Thepocketed sides of each web are joined, interdigitated or tessellated toform a laminate having two flat sides.

In other embodiments of the invention, the laminate formed by joiningthe two webs is laminated with a metallic foil or metallized polymericfilm.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

Preferred embodiments of the invention are disclosed hereinbelow withreference to the drawings, wherein:

FIG. 1 is a plan view of one embodiment of a web formed in accordancewith the teachings of the present invention;

FIG. 2 is an end view of one embodiment of a laminate formed inaccordance with the teachings of the present invention; and

FIG. 3 is a schematic top plan view illustrating the arrangement ofpockets in the laminate of FIG. 2.

DETAILED DESCRIPTION OF THE INVENTION

As shown in FIG. 1, a web 10 is formed from two sheets of polymermaterial. An upper sheet 11 includes vacuum-formed pockets 12. Thepockets 12 may take any shape and are shown as being square for thepurposes of the present example. Accordingly, the perimeter 13 of eachpocket may take practically any form. The upper surface 14 and perimeterwalls 15 of each pocket are integrally formed by a vacuum or othermolding process into the upper sheet 11. The upper sheet 11 issubsequently bonded to a lower sheet 16, which operation causes thesealing of each of the pockets 12. With reference to FIG. 1 it can beseen that the pockets 12 form a regular two-dimensional array which maybe conveniently viewed as having any number of rows R and columns C.Pockets 12 in any row or column have the same spacing, but adjacent rowsR (or columns C, or both) are offset by an amount 0 so as to form aregular array of pockets 12 and gaps 17.

In preferred embodiments of the invention, a gap 17 is formed betweenadjacent pockets 12. The gap 17 is large enough to accommodate a pocket12.

As shown in FIG. 2, two webs 11, 20 may be assembled and optionallyjoined to form a laminate 21. Owing to the arrangement of the webs 11disclosed with reference to FIG. 1, the pockets 12 face one another,interdigitate or tessellate to form a compact structure. As shown inFIG. 2 and with respect to a row of pockets 12, pockets of the top layerare seen as alternating with pockets of the bottom layer. The webs 11,20 may be sealed together, or not.

FIG. 3 illustrates a laminate 21 with internal pockets 12 of the varietydepicted in FIG. 2. It will be appreciated that the array of pockets isshown as relatively closely packed with only small gaps G between anytwo adjacent pockets 12. It will appreciated that the size and spacingof the pockets may be altered to achieve different packing densities,laminate stiffness, impact or sound absorbing qualities. Neither thegaps 17, nor the pockets 12 need all be the same size so long as thepockets interdigitate or tessellate to form a compact structure withparallel outside surfaces 23, 24.

Another embodiment of the invention is suggested in FIGS. 1 and 2. Inthis embodiment, the outside surface of one web 23 or both 23, 24 areprovided with enhanced properties by further lamination with a metallicfoil or metallized polymeric film 30. The application of, for example,an aluminum foil or aluminum powder coated polyester film 30 providesimproved insulation and provides for the reflection of radiant heatenergy.

The structures of the present invention have a wide variety of uses.Single webs of the type depicted in FIG. 1 may be used for vibrationisolation, impact protection and as noise insulation. A web of this typefurther laminated with the metal foil or film 30 serves as a betterthermal insulator. Webs which are laminated together 21, as shown inFIG. 2, may be used as sound or noise insulation and may be engineeredwith a fixed, predetermined gap A between webs which optimizes noiseabatement and particular frequencies or otherwise provides for betterinsulation. The gap A may be filled with a foam or gas (air or othergas) or liquid.

While the present invention has been disclosed with reference toparticular details of construction, these should be understood as havingbeen provided by way of example and not as limitations to the scope orspirit of the invention. In particular, the dimension, shape and depthof the pockets is not considered essential to the utility of theinvention. Similarly, the materials of construction and the precisemethods of lamination are not considered essential.

1. A composite material comprising: a first web and a second web,wherein each of the first and second webs includes, respectively, afirst sheet and a second sheet, with the first sheet of each web beingcomposed of polymeric material, the first sheet having an array ofsimilar air-filled closed pockets formed into the first sheet withadjacent pockets being spaced apart from one another enough toaccommodate a similar pocket; wherein each second sheet of each web isbonded to the first sheet of the respective web so as to seal thepockets of each respective first sheet; wherein the first and secondwebs are assembled to form a composite structure with the pockets ofeach web facing one another and interdigitating; wherein the first andsecond webs are spaced apart by a gap of fixed dimension; and whereinthe gap is filled with a substance selected from: foam, liquid, air, orgas other than air.
 2. The composite material of claim 1 wherein thepockets of each web tessellate.
 3. The composite material of claim 1wherein the pockets of both webs form a compact structure.
 4. Thecomposite material of claim 1 wherein the first and second webs arejoined together.
 5. The composite material according to claim 1 whereina metallic foil is bonded to an outside surface of the second sheet ofthe first web.
 6. The composite material according to claim 1 whereinthe pockets of each web are arranged in an array of rows and columns,and adjacent rows or columns are offset with respect to one another. 7.A composite material comprising: a first web and a second web, whereineach of the first and second webs includes, respectively, a first sheetand a second sheet, with the first sheet of each web being composed ofpolymeric material, the first sheet having an array of similarair-filled closed pockets formed into the first sheet with adjacentpockets being spaced apart from one another enough to accommodate asimilar pocket, with a metallic material bonded to an outside surface ofthe second sheet of the first web; and wherein the first and second websare assembled to form a composite structure with the pockets of each webfacing one another and interdigitating, with the first and second websbeing spaced apart by a gap of fixed dimension, wherein the gap isfilled with a substance selected from: foam, liquid, air, or gas otherthan air.
 8. The composite material of claim 7 wherein the metallicmaterial is a metallic foil.
 9. The composite material of claim 7wherein the metallic material is a metallized polymeric film.
 10. Thecomposite material of claim 7 wherein the first and second webs arejoined together.
 11. The composite material of claim 7 wherein thepockets of both webs form a compact structure.